This invention relates to a computer system equipped with a first storage system, a second storage system, a host computer, and a management computer, and to a technology for writing data in the first storage system and in the second storage system.
In recent years, data used in a computer system of a company or the like has been growing in importance. Thus, a data protection technology is applied to the computer system. The data protection technology is for recovering data in a faulty computer system. For example, the data protection technology includes a remote copying technology.
An example of the remote copying technology is disclosed in JP 2005-18506 A. According to the remote copying technology, a first storage system stores data received from a host computer. The first storage system transmits data received from the host computer to a second storage system arranged at a physically separated place. The second storage system stores the data received from the first storage system. Even when a fault occurs, the computer system to which the remote copying technology is applied can recover from the fault within a relatively short time. To be specific, the computer system to which the remote copying technology is applied recovers from the fault by using the data stored in the second storage system.
An identification control technology of a plurality of volumes is disclosed in JP 2000-330924 A. A host computer identifies two different volumes accessed through two different paths as identical volumes. Accordingly, even when a fault occurs in one of the paths, the host computer can access data by using the other path.